Method of preservation, packaging and molding of fresh foods for human use



United States Patent Ofiice 3,359,122 Patented Dec. 19, 1967 3,359,122METHOD OF PRESERVATION, PACKAGING AND MOLDING OF FRESH FOODS FOR HUMANUSE Ralph S. Zebarth and Richard A. Braeking, Kansas City, Mo.,assignors to Gordon Johnson Company, Kansas City, Mo., a corporation ofMissouri No Drawing. Continuation of application Ser. No. 266,-

061, Mar. 18, 1963. This application Dec. 13, 1966, Ser. No. 601,434

5 Claims. (Cl. 99-194) This application is a continuation of Ser. No.266,061, filed Mar. 18, 1963, now abandoned.

This invention relates to the preparation and processing of perishableproducts, and more particularly, to the preservation, at loweredtemperatures, of articles for use as human foods, a primary object beingto increase their storage life, to preserve their nutritional value andto provide a novel method of proper preparation, packaging, cold storageand transportation under refrigeration of such foods in a mannerappreciably more sanitary and less expensive than has heretofore beenpossible by conventional methods.

Economic and material losses because of deterioration and spoilage arevery large in the food industry. Many of these losses can be preventedby exercising care and control in the preservation, packaging andholding of food products. It is, therefore, a most important object ofthe instant invention to improve the keeping quality of animal foods byslowing down physical and chemical changes therein prior to its reachingthe ultimate consumer, utilizing a method which results in lowering thespeed at which food-spoiling chemical reactions take place, slowing downthe rate of enzyme action, preventing discoloration and the growth ofmany harmful microorganisms, and reducing the chances of contaminationand adulteration during handling.

Another important object of the present invention is the provision of amethod of chilling preservation capable of improving and retaining thetexture, flavor and appearance of the resulting food product while, atthe same time, reducing costs, labor and other problems for allhandlers, including the processor, the carrier, the wholesaler, theretailer and the housewife.

Stored animal foods tend to quickly change in form and color, developbad odors and flavors, oxidize and dehydrate, turn rancid and develop anold appearance and taste. Such changes are hazardous when the productbecomes poisonous or toxic, necessitating the prevention of the actionof deleterious organisms on the food. Uppermost in importance then isthat the product be preserved, packed and held pursuant to our methodunder sanitary conditions. It must be delivered to the ultimate consumerin complete absence of any filthy, putrid or decomposed substance. Thepoultry carcass and all parts thereof must in no way be contaminated oradulterated, or otherwise become injurious to health.

While the present invention is especially valuable in the processing andpackaging of ready-to-cook poultry and edible products thereof, itsrange of use is by no means so limited. We contemplate its adaption tothe entire field of animal foods for human consumption, including themeat of cattle and calves, sheep, swine and goats, and the edibleproducts derived from their carcasses. Wild animals, fish and game arealso not to be deemed as excluded from the concepts of the invention.

Ease of description and understanding of the invention suggests,however, the limitation to a single product; hence, the method willhereinafter be set forth in the sense of commencing with ready-to-cookpoultry. By this we shall mean any dressed poultry that is ready to cookwithout need of further processing, including any cutup or disjointedportion of poultry or any edible part thereof. Such birds as chicken,turkeys, ducks, geese and guineas are, of course, understood to beincluded Within the term poultry.

Poultry processing has grown rapidly and become one of the largest foodindustries, primarily because of the relatively recent development ofsanitary and economical methods of dressing and subsequent handling ofthe dressed birds. It is recognized that such growth has been the resultin part of the adoption of modern methods of food preservation, such ascold storage, canning, freezing, drying and curing. There remains,however, the demand for freshly dressed poultry wherein appearance andtaste remain unaltered; this has, therefore, heretofore necessitatedrapid handling and fast transportation between the time of dressing andthe moment when the product is placed before the purchasing public.

To accomplish these results, it is the universal practice to utilize icepacking as the primary method of preventing spoilage during the delaythat is necessary before the freshly dressed birds are in the hands ofthe consumer. This method is by no means fully satisfactory and presentsmany problems not heretofore solved.

Ice packing is an expensive and laborious task. It is by no means assanitary as might be desired. Spoilage takes place much too frequentlyunless extreme care is exercised, not only in initial packingprocedures, but throughout the time the product must remain in the icedcondition. It is not dependable as a method of preservation because thevarious groups who handle the product cannot be expected, at all times,to continue to follow necessary and strict procedures for preventingspoilage, contamination and adulteration.

Melting of the ice in refrigerated holding rooms and transportation carsand trucks presents a messy and unwholesome condition. Ice-packcontainers become watersoaked, soggy and moldy. And finally, unpacking,and the results of thawing of the ice pack, presents many problems,including waste of time, labor and materials, and requires properfacilities and other increased handling costs.

There is presented, therefore, a definite health hazard because it isimpossible to avoid contamination and undiscovered spoilage as theresult of such continual handling of the product during the steps whichmust be taken between packing and final sale. Also, to some extent atleast, bacterial growth continues and becomes dangerously rapid inexposed or melted areas of the shipping package. Additionally, the icepack method of packaging is not altogether satisfactory from thestandpoint of preservation of taste, texture, nutritional value,palatability and fresh appearance.

In accordance with the principles of the present invention, therefore,it is proposed to place freshly dressed poultry on the market, properlypreserved and in a sanitary condition, without any need for ice packingwhatsoever. To accomplish the desired results in the method about to bedescribed, speed becomes a factor at the processing plant immediatelyfollowing the dressing operations, rather than between the time ofinitial ice packing and the time the product is unpacked and presentedfor sale to the consumer, as has heretofore been the necessary practice.Additionally, all steps in the method are desirably carried out as arapid and continuous process without substantial interruption or delay.

Rapid multiplication of microorganisms at Warm temperatures can beprevented by rapid chilling. Since about 15 minutes must be allowed forscalding and defeathering, and another 15 minutes for evisceration, thefirst chilling step must, therefore, for best results, take placeimmediately after the poultry is dressed. The holding period afterkilling and before chilling is most critical since birds held too longat high temperatures deteriorate in flavor, develop off-odors, and moreimportant, undergo rapid changes which increase the chances of earlyspoilage. Chilling should be commenced before any appreciable chemicalor physical change by organisms or other action, and prior tocontamination of the clean product, which might occur if other handlingsteps were permit ted to intervene. Wholesomeness is an extremelyimportant factor, contemplating that the product be sound, healthful,clean and otherwise fit for human food.

This first step consists then in reducing the temperature of the dressedand ready-to-cook poultry in accordance with operating practices whichwill at least insure removal of the animal heat as quickly as possibleafter dressing and at the same time preserve the condition andwholesomeness of the product.

It is not possible to provide an exact definition of quick-chilling orto set any hard and fast rules as to the amount of heat that should beremoved in the first chilling step. Basically, however, it must berecognized that undesirable changes takes place in the tissues ofpoultry in slow chilling, causing it to leak when the temperature isultimately raised prior to cooking. Manifestly, such leakage results inundesirable changes in texture and should be avoided as much aspossible.

Furthermore, during slow chilling, the temperature of the poultry maynot be reduced fast enough to prevent spoil-age. Hence, as herein used,the term quick-chilling may be considered the step which cools thepoultry sufficiently and fast enough to prevent spoilage and permits aminimum change in the food tissues. This shall, there fore, beunderstood to mean cooling immediately after processing, and preferablyprior to packaging, so that the internal temperature is reduced to atleast 40 F.

Presently available commercial methods of quickchilling which haveproved to be both economical and sanitary, provide for advancement andtumbling of the birds in a tank of low-temperature water, commonlyreferred to as ice-water chilling. U.S. Letters Patent No. 2,942,429 ofJune 28, 1960, and U.S. application Ser. No. 749,804, now U.S. Patent3,092,975 issued June 11, 1963, are incorporated herein by reference, asnecessary for a full understanding of such chilling equipment andmethods. The time and temperature examples and the operating procedurestherein disclosed are adopted herein as satisfactory in carrying out thefirst step of the process of the instant invention.

Ideally, however, as contemplated by our novel method, the firstchilling step should be completed in a matter of minutes and lower theinternal temperature of the carcass well below 40 F. More practically,however, because of such factors as economy, it is to be expected thatfrom to 45 minutes might be consumed in this step for chickens, to about2 hours for turkeys, until the temperature is reduced at least to below40 F., but not necessarily lower than 32 F., is. within the range of 33F. to 40 F. If such approximate time-temperature factors are followed,the quick-chilling definition above set down, will be adequately met inaccordance with the principles of the method of the instant invention.Heavier birds often dress-out even above the normal body temperature of107 F. because of scalding; this, of course, increases the time neededin the first chilling step.

While the first step of the method herein described is, of course, notlimited to such cold water bath procedures, when followed, it may bedesirable at times to provide as a second step, the draining of excesswater from the poultry as it emerges from the bath. But here again, thisstep need not and should not consume an appreciable amount oftime-possibly 2 or 3 minutes for chickens, to about 15 minutes forturkeys, before commencement of the third step. The temperature of theproduct should not rise to any great extent following quick chilling andcertainly not to the extent of permitting leakage of nutritionallyvaluable body fluids that add to product flavor and are rich inproteins, minerals and vitamins. Actually, a thin coating of ice on theproduct during holding and shipment is not objectionable; on thecontrary, the ice coatings help retain texture and flavor during storageand prevent dehydration.

In this connection, it should be emphasized at this juncture thatpoultry processing methods must insure that nutritional values areretained. High quality processed poultry, preserved for subsequent use,must compare favorably with cooked fresh foods in protein, mineral andvitamin content and in other nutrient qualities. It must be realizedthat any treatment causes some losses, particularly where the processedproduct must be kept for long periods before being used. It cannot beunduly stressed, therefore, that both from the standard of appearanceand keeping quality, these important factors must be considered in thepresent method. Preservation of food values requires the avoidance offluid leakage throughout the process as distinguished from excessivedrainage of such fluids which should, on the other hand, be properlytrapped within the body cells and tissues until ready for cooking andserving.

Hence, the process continues rapidly and without interruption to anotherquick-chilhng step which might properly be called deep-chilling toprovide terminology for distinguishing it from the first step abovedescribed.

It should be explained at this point that health authorities today havegenerally recognized that the growth of most disease-producing bacteriain poultry is sufficiently impeded to control health hazards if thetemperature is reduced to below 40 F.

Much lower temperatures are, however, desirable and are necessary toaccomplish the results herein contemplated. Also, it is entirelypossible to go well below 40 F. and still provide the public with whatis properly called freshly dressed poultry as distinguished from frozen,canned or other methods of preservation.

Thus, in the deep-chill step, the temperature is dropped to within areasonable range below the freezing point of water, for example, betweenabout 28 and 32 F. It is important to note here that this temperaturereduction step does not in any manner contemplate freezing because, asabove indicated, there must be a sharp and well defined distinction onthe market between freshly dressed and frozen poultry. It is necessaryto lower the temperature to about 28 F. before poultry can be properlyconsidered a frozen food product or in a solidly frozen state. Thefreezing point of the product as a whole may properly be considered tobe within the range of about 27 F. to about 29 F., depending on thesize, type and age of the bird and its constituents, as distinguishedfrom the freezing point of the individual parts, compomeats andsolutions thereof, which vary along a wider range below 32 F. Hence, theonly ice-forming crystals to be found in the product produced by ourmethod will be those produced on and near the surfaces of the product asthe result of light freezing of moisture in the form of free water.

I outstandingly important and valuable, however, is the fact that thefood content of the product is adequately preserved within suchtemperature range, resulting in all of the benefits of spoilageprevention and conservation of nutritional values above explained.

For the most part, the deep chill step may be carried out commerciallyby either of at least two general procedures. The first of theseinvolves the system of advancement (by immersion and/or spray chilling)through a refrigerated solution as disclosed in U.S. Patents Nos.3,006,774 of Oct. 31, 1961, and 3,043,319 of July 10, 1962. See alsoU.S. Patent No. 2,372,373 of Mar. 27, 1945. The solutions thereindisclosed, and others which might well be used in this step, may be ofsuch nature however, that the poultry must be covered, necessitatingstill another step immediately preceding deep chilling.

Since health and sanitation regulations preclude actual contact of thepoultry with certain of such solutions, bags or other containers must beemployed. Bags made from plastic and other materials substantiallyimpervious to the solutions have been found to be quite satisfactory.Each whole bird may be packaged individually in its own bag, if desired,whereupon, after proper closing and sealll'lg of the bag, the packagemay be subjected to the cooling solutions without danger of adulterationor contamination. Alternately, as many as a dozen or more birds, forexample, may be packaged in a larger bag of similar material selected towithstand considerable abuse in handling.

Still another packaging method which might well be used to advantageprior to the deep-chill step employs a telescoped container such asillustrated in U.S. Patent No. D. 189,379, of Nov. 29, 1960, heatsealed, for example by the method and sealer set forth in U.S. PatentNo. 3,071,906 of Jan. 8, 1963. This package has particular value for usein poultry that is cut up into parts prior to the step of deep chilling.

Additionally, poultry parts may be packed through use of a plastic filmsealed thereover or be placed in a suitable tray and then enveloped in afilm or bag, sealing in both the tray and the product.

There are, of course, many other kinds of moisturevapor-proof wrappingsand packages capable of protecting the product during storage so that itwill retain proper appearance, will not lose moisture and will not besubjected to contamination and adulteration as the result of handlingand other adverse conditions that are not conducive to sanitation andwholesomeness. Not to be overlooked also, is the random and loosepackaging of poultry parts in containers as distinguished from packingin preselected order in trays.

The water content of poultry meat may range from about 71% for broilerswith a 7% fat content, to about 56% for hens having a 25% fat content.Hence, there is a direct economic disadvantage in shrinkage from loss ofthis water content by dehydration during improper processing, chilling,packaging and holding steps. Loss of water also results in appearancechanges, loss of nutrients and flavor and reduction in consumeracceptance. Here again then, leakage and dehydration can be reduced to aminimum by packaging in material that is reasonably moistureimpermeable.

A second procedure which may be followed obviates the necessity ofpre-packaging since it uses a refrigerant that has no inherent danger ofcontamination. It uses a conveyor belt, a screw conveyor, or other meansof rapid and continuous advancement of the product through an insulatedtunnel wherein carbon dioxide gas is released to shower over the productat a rate and over a short period of time (conceivably within a matterof seconds) to attain the deep-chill temperatures above suggested.

Many other methods, such as air blast chilling wherein, for example,the'air temperatures could range from -20 F. to 40 F., might well beused provided that the step can be carried out quickly and economicallyon a commercially profitable basis. The time factor remains importantand it is usually not feasible to permit more than from about 20 to 30minutes to be consumed in the deep chilling step of the method of thepresent invention.

In both chilling steps, the duration of immersion may, of course, bedecreased to some extent as the temperature of the coolant is reduced.Manifest also is the fact that the time-temperature combination willvary with the kind, age and class of poultry being processed.

Any other chilling procedures (for either or both of the chilling stepsabove outlined) which will effect chilling in a manner equal to thatobtained by the procedures hereinabove set forth, may be employed tocarry out the method of our instant invention. The important factor isto lower the temperature of the product so that it will temper out atabout 30 F. plus or minus 2 degrees when subsequently held, shipped andstored at approximately 30 F. Tests have indicated that a 4 to 5 poundbird, previously chilled to 32 to 40 F., subjected to the deep-chillstep of our method will, in 15 to 18 minutes have a surface temperatureof 0 to 5 R, an outer marginal temperature of about 20 F., and aninternal temperature of about 34 F. When held in cold storage at 28 to32 F., it will temper out to 30 F. throughout in 2 to 3 hours.

In summary, then, the product should be allowed to temper out to a finaltemperature below the freezing point of water and above the freezingpoint of the flesh of the product.

No time should be lost in now advancing the product to a point where theattained deep-chill temperatures are maintained. For the most part, thedaily output of many poultry processing plants is conveyed directly torefrigerated trucks for rapid transportation to markets and sale withina matter of hours or but a days delay. Others utilize refrigeratedholding rooms for at least a part of such out ut.

In any event, it is neither difiicult nor expensive to maintain thespace in which the poultry is stored or transported at temperatureswhich will insure maintenance of within about a 28 F. to 32 F. range.

As thus far outlined, the method involves the quickchill step, possiblyfollowed by draining if excess moisture removal is deemed necessary ordesirable, then the deepchill step and finally the step of maintainingthe attained temperature, preferably until sold to the ultimateconsumer. The method also calls for packaging either before or afterchilling, or between the two chilling steps, for purposes of moistureretention and sanitation regardless of whether or not the packaging isneeded to also protect the product from the chilling solutions orsubstances.

It is to be made clear, however, that the attainment of the temperaturewherein the pro-duct tempers out at about 28 to 32 F. need not be twodistinct steps. In-

stead, the freshly dressed product may be continually and rapidlychilled as a single step and then packaged for holding or shipment.

While sources of bacterial contamination in poultry include theenvironment of the live bird and the processing steps from killing tocomplete dressing, one of the greatest bacterial hazards is themarketing of chilled ready-tocook poultry. After about one week at usualcommercial holding temperatures, bacterial spoilage normally renders theproduct unacceptable.

It can be expected, on the other hand, that poultry Will be good forthree or more weeks under our method if held substantially at 30 F. Itis to be recognized, however, that the maintenance of the propertemperature can be fully followed only to the extent that-those usingthe method have control of the product. The processor can, of course,easily adhere to this last step in holding rooms prior to shipment. And,it can be expected that the carrier Will fully cooperate.

' Unloading by the carrier, at the wholesale level might result in somewarming of the product, especially under adverse weather conditions, butfor the most part the product will still be in good condition by thetime it is within the cold storage facilities of the wholesaler.Delivery of the product by the wholesaler to the retailer may not alwaystake place in refrigerated vehicles, but the time factor is not usuallyso great as to present any grave problem. Finally, at the retail level,proper storage and display facilities are today quite normal, with theresult that the product can be placed in the hands of the customer atabout the same temperature as it had immediately prior to shipment fromthe processor. Hence, there is a considerable safety factor in themethod, permitting a certain amount of sub-standard handling betweenprocessor and housewife.

The packaging step can and will vary considerably. In some instances,the processor will place the product in the consumer package, enclosedfor the purpose of display and sale to household consumers. At othertimes, the immediate container may not be the consumer package but someother enclosure in which the product is packed. Then, of course, it isto be expected that shipping containers will be employed for receivingeither the immediate containers or the consumer packages. For example,if a dozen birds are placed in an immediate container such as a singleplastic bag, a number of such bags may in turn be placed in a shippingcontainer made from wood, cardboard or other material.

Finally, while chilling, as a single, continuous step, has beenhereinabove mentioned, sanitation still remains the most importantfactor. The first chilling step, ahead of the deep-chill step is,therefore,'to be preferred because, as disclosed in said applicationSerial No. 749,804, cleaning of the product and prevention ofdehydration are salient features of the equipment and the method thereindisclosed.

Immediate Wet chilling also has the advantage of reducing or preventingdiscoloration. Slush ice cooling removes animal heat rapidly, reducesshrink and has a bleaching effect that improves the finish of the bird,resulting in a bright, fresh-appearing product.

Furthermore, We consider the packaging step of our present method to beimportant from a sanitation and a moisture retention standpoint. Suchstep is much easier and more practical at the end of the quick-chillstep, when the muscles and flesh of the bird are still rather soft andpliable, than after the deep-chill step. We have found also thateconomies tend to dictate that all three steps be followed, and in thatorder, with emphasis on three factorslowered temperatures, rapidhandling and good sanitation in order to maintain quality throughout allchannels of marketing.

It is now abundantly clear and can be fully appreciated that the instantmethod has many advantages over conventional ice pack procedures,resulting in a decidedly better product and increased profits for thefood processing industry generally. Excellent consumer acceptance ofpoultry, marketed after processing in accordance with the presentinvention, can be expected, since it will have no evidence ofdeterioration during storage and will have retained its fresh surfaceappearance, flavor, tenderness and palatability. Tremendous yearlysavings in reduced spoilage and deterioration can thus be passed on tothe consumers with better quality and at a lower cost.

What is claimed is:

1. A method of preservation and packaging of poultry comprising thesteps of:

chilling freshly dressed poultry to a temperature for preventing rapidgrowth of most harmful, pathogenic, disease-producing bactteria;thereupon lowering the temperature of the poultry to within a range ofapproximately 28 F. to 32 F. to freeze the free water on the surface ofthe poultry without freezing the tissues thereof; and

packing a plurality of individual units of said poultry in a singleshipping container.

2. A method of preservation, packaging and holding of poultry comprisingthe steps of:

chilling freshly dressed poultry to a temperature for preventing rapidgrowth of most harmful, pathogenic, disease-producing bacteria;thereupon lowering the temperature of the poultry to within a range ofapproximately 28 F. to 32. F. to freeze the free water on the surface ofthe poultry without freezing the tissues thereof;

packing a plurality of individual units of said poultry in a singleshipping container; and maintaining the poultry at the attainedtemperature during storage and shipment. 3. A method of preservation,packaging and holding poultry comprising the steps of:

10 chilling freshly dressed poultry in a cold water bath to clean thesame until the temperature thereof is lowered sufficiently to preventrapid growth of most harmful, pathogenic, disease-producing bacteria;

5 thereupon packaging individual units of said poultry in separatecontainers to protect the same from contamination and adulteration andto prevent dehydration; then lowering the temperature of the poultry towithin a range of approximately 28 F. to 32 F. to freeze the free Wateron the packaged poultry without freezing its tissues and other bodyfluids; and finally placing the packaged poultry in cold storage at theattained temperature until the same is marketed. 4. A method ofpreservation of meat comprising the steps of:

removing heat from freshly dressed meat until rapid growth of mostharmful, pathogenic, disease-producing bacteria is prevented; thereupon30 subjecting the meat to a temperature maintained at least as low as 32F. to freeze the free Water on the surface of the meat without freezingits tissues and other body fluids, and then, subjecting the meat to atemperature maintained at ap- 35 proximately 28 F. to 32 F. to cause themeat to temper out below 32 F. and above 28 F. 5. A method ofpreservation of poultry comprising the steps of:

chilling freshly dressed poultry to a temperature for preventing rapidgrowth of most harmful, pathogenic,

disease-producing bacteria; thereupon subjecting the poultry to acooling medium having a temperature within a range of approximately 28F. to 32 -F. to freeze the free water on the surface of (the poultryWithout freezing the tissues thereof;

an then placing the poultry in cold storage maintained at a temperatureof approximately 28 F. to 32 F. to cause the poultry to temper out below32 F. and

above 28 F.

References Cited UNITED STATES PATENTS 1,322,312 11/1919 Larsen 991942,329,226 9/1943 Stafford et al. 99l94 2,860,056 11/ 1958 Bradford99-194 2,942,429 6/1960 Van Dolah et al. 99l94 3,111,412 11/1963 Mouk99195 OTHER REFERENCES 616,511 2/1961 Canada.

A. LOUIS MONACELL, Primary Examiner.

L. M. SHAPIRO, Assistant Examiner.

Disclaimer 3,359,122.Ralph 1S. Zebarth and Richard A. Braeking, KansasCity, Mo.

METHOD OF PRESERVATION, PACKAGING AND MOLD- ING OF FRESH FOODS FOR HUMANUSE. Patent dated Dec. 19, 1967. Disclaimer filed Sept. 15, 1971, by theassignee, Gordon J 01mson Company. Hereby enters this disclaimer toclaims 1-5, inclusive, of said patent.

[Ofiicial Gazette January 25, 1.972.]

1. A METHOD OF PRESERVATION AND PACKAGING OF POULTRY COMPRISING THESTEPS OF: CHILLING FRESHLY DRESSED POULTRY TO A TEMPERATURE FORPREVENTING RAPID GROWTH OF MOST HARMFUL, PATHOGENIC, DISEASE-PRODUCINGBACTTERIA; THEREUPON LOWERING THE TEMPERATURE OF THE POULTRY TO WITHIN ARANGE OF APPROXIMATELY 28*F. TO 32*F.TO FREEZE THE FREE WATER ON THESURFACE OF THE POULTRY WITHOUT FREEZING THE TISSUES THEREOF; AND PACKINGA PLURALITY OF INDIVIDUAL UNITS OF SAID POULTRY IN A SINGLE SHIPPINGCONTAINER.